The just-so stories are written by Terence Kealey who bills himself as vice-chancellor of Buckingham University. (He's also a clinical biochemist.) The stories were published on Times Online as: Guys, be glad to be grey or thinning on top.

Here's are the funny parts ....

We human beings, too, are highly selected sexually, but in our case it is women who are the peacocks: the more beautiful they are, the greater the number and quality of the men who court them. This is why, some 75,000 years ago, we made our last two evolutionary advances: we lost our body hair and we invented art.

...

Art and hairlessness co-evolved because they fed off each other. The girl whose skin was least hairy could paint it, tattoo it, decorate it and clothe it more adventurously than could her furry sisters. So she got more and better men. And in consequence her children - even the males, though to a lesser degree - lost their hair too. We had become the naked ape.

This was all supposed to happen about 75,000 years ago, according to Terence Kealey. It's interesting to speculate on what must have happened.

Small groups of hunter-gatherers met from time to time. Almost all the females probably had sexual partners when they were all hairy. It's unlikely that there were many females who couldn't find a mate.

All of a sudden, there were some new girls on the block. They had less hair and they covered their body with paint and tattoos. These mutants were so attractive to men that they were preferentially chosen as mates and, more importantly, their hairy sisters were ignored. The hairy women didn't have offspring so there must have been quite a few men who were celibate as well. (Unless the mutants had multiple mates.)

That's why hairlessness was rapidly selected.1

In order to understand the next just-so story you have to know that the article begins with an explanation of why Silvio Berlusconi, the Prime Minister of Italy, had a hair transplant.

Which brings us back to Mr Berlusconi. Hair plays a social signalling role in many older mammals. It goes grey - which can be a good thing. It is only the silverback gorilla(so-called named for obvious reasons) who can corral a harem of females, in part because gorillas of both sexes revere older males. We have retained our head hair so enabling that social signalling: grey hair on men can reinforce an alpha message of chiefdom. As can baldness.

Men have evolved to attract women. Because only some men go bald, we must assume that different women are attracted differently. Some women will be attracted to young men, but young men are untried and therefore risky, so some women will seek sugar daddies instead. Mating with sugar daddies invokes a different set of risks but the trophy wife is nonetheless making a rational choice - one that may well have been rewarded preferentially in the Stone Age - to which she is in part guided by baldness in her man.

Now, what sort of girl will fancy Mr Berlusconi? Clearly the sugar daddy type. But such a girl will subconsciously be looking for baldness in her beau and she may be put off by the mixed messages Silvio's head is transmitting.

The biology of baldness is complex. Some theorists believe that it renders older men so unattractive that - rather than sowing additional wild oats - they are forced to spend more time with their families and so help their children to survive. But the myriad Becky Sharps in literature and history help to disprove that theory.

Now let's imagine that we are back in the stone age. There are a bunch of men who, for undisclosed reasons, have reached the age of fifty and don't have a mate.2 There are a number of young women who want an older man for a mate instead of the young men who are probably available.

Most of the fifty year olds have hair that's the same color it has always been. All of a sudden a few mutants appear who have white hair or (gasp!) no hair at all. These older men become so sexually attractive to the young women that they get to reproduce while their hairy friends are spurned. Maybe they painted or tattooed their bald heads. Yes, that would work. I think I'll try it.

That's how the alleles for baldness and white hair get selected in ancient hunter-gatherer societies.

1. It's a good thing that razors hadn't been invented, otherwise the hairy women could have fooled the men into thinking they were a hairless mutant.

2. I'm assuming monogamy as the default option. As far as I know, this is generally accepted.

Matt Ridley's explanations of sexual selection in The Red Queen are a bit more logical... might not women happen to be attracted to bald men because those particular men also have power, money, or some other favourable characteristic? The balding/grey explanation is complete tripe... but you aptly pointed that out already.

Monogamy as the default option seems to be accepted as the choice of the female, as a strategy for greater reproductive success. They want their man monogamous so he cares for the child... whether or not the child bears his genes is a different story. For a male, polygamy is a better strategy because he can pass on more of his genes, without the energetic investment in parenting that the female has to make.

@ Anonymous> The discussion doesn't refer to conscious consideration of sex or passing on your own genes, especially the latter, but rather the unconscious drive to reproduce. You may consciously not care about sex, but there's a significant part of your subconscious that still wants it, barring what would have to be considered a psychological disorder. If your ancestors hadn't had an interest in sex at some level, we wouldn't be discussing this. @ the first anonymous> Are you asking why baldness occurs? It's a sex-linked trait. The recessive gene for male pattern baldness can be found on the X chromosome, so it's passed through the female line (your mom's father should be bald also) without affecting the female.Shame on your HS bio teacher for never covering that, if they didn't.

Laurence A. Moran

Larry Moran is a Professor Emeritus in the Department of Biochemistry at the University of Toronto. You can contact him by looking up his email address on the University of Toronto website.

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Quotations

The old argument of design in nature, as given by Paley, which formerly seemed to me to be so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being, like the hinge of a door by man. There seems to be no more design in the variability of organic beings and in the action of natural selection, than in the course which the wind blows.Charles Darwin (c1880)Although I am fully convinced of the truth of the views given in this volume, I by no means expect to convince experienced naturalists whose minds are stocked with a multitude of facts all viewed, during a long course of years, from a point of view directly opposite to mine. It is so easy to hide our ignorance under such expressions as "plan of creation," "unity of design," etc., and to think that we give an explanation when we only restate a fact. Any one whose disposition leads him to attach more weight to unexplained difficulties than to the explanation of a certain number of facts will certainly reject the theory.

Charles Darwin (1859)Science reveals where religion conceals. Where religion purports to explain, it actually resorts to tautology. To assert that "God did it" is no more than an admission of ignorance dressed deceitfully as an explanation...

Quotations

The world is not inhabited exclusively by fools, and when a subject arouses intense interest, as this one has, something other than semantics is usually at stake.
Stephen Jay Gould (1982)
I have championed contingency, and will continue to do so, because its large realm and legitimate claims have been so poorly attended by evolutionary scientists who cannot discern the beat of this different drummer while their brains and ears remain tuned to only the sounds of general theory.
Stephen Jay Gould (2002) p.1339
The essence of Darwinism lies in its claim that natural selection creates the fit. Variation is ubiquitous and random in direction. It supplies raw material only. Natural selection directs the course of evolutionary change.
Stephen Jay Gould (1977)
Rudyard Kipling asked how the leopard got its spots, the rhino its wrinkled skin. He called his answers "just-so stories." When evolutionists try to explain form and behavior, they also tell just-so stories—and the agent is natural selection. Virtuosity in invention replaces testability as the criterion for acceptance.
Stephen Jay Gould (1980)
Since 'change of gene frequencies in populations' is the 'official' definition of evolution, randomness has transgressed Darwin's border and asserted itself as an agent of evolutionary change.
Stephen Jay Gould (1983) p.335
The first commandment for all versions of NOMA might be summarized by stating: "Thou shalt not mix the magisteria by claiming that God directly ordains important events in the history of nature by special interference knowable only through revelation and not accessible to science." In common parlance, we refer to such special interference as "miracle"—operationally defined as a unique and temporary suspension of natural law to reorder the facts of nature by divine fiat.
Stephen Jay Gould (1999) p.84

Quotations

My own view is that conclusions about the evolution of human behavior should be based on research at least as rigorous as that used in studying nonhuman animals. And if you read the animal behavior journals, you'll see that this requirement sets the bar pretty high, so that many assertions about evolutionary psychology sink without a trace.

Jerry Coyne
Why Evolution Is TrueI once made the remark that two things disappeared in 1990: one was communism, the other was biochemistry and that only one of them should be allowed to come back.

Sydney Brenner
TIBS Dec. 2000
It is naïve to think that if a species' environment changes the species must adapt or else become extinct.... Just as a changed environment need not set in motion selection for new adaptations, new adaptations may evolve in an unchanging environment if new mutations arise that are superior to any pre-existing variations

Douglas Futuyma
One of the most frightening things in the Western world, and in this country in particular, is the number of people who believe in things that are scientifically false. If someone tells me that the earth is less than 10,000 years old, in my opinion he should see a psychiatrist.

Francis Crick
There will be no difficulty in computers being adapted to biology. There will be luddites. But they will be buried.

Sydney Brenner
An atheist before Darwin could have said, following Hume: 'I have no explanation for complex biological design. All I know is that God isn't a good explanation, so we must wait and hope that somebody comes up with a better one.' I can't help feeling that such a position, though logically sound, would have left one feeling pretty unsatisfied, and that although atheism might have been logically tenable before Darwin, Darwin made it possible to be an intellectually fulfilled atheist

Richard Dawkins
Another curious aspect of the theory of evolution is that everybody thinks he understand it. I mean philosophers, social scientists, and so on. While in fact very few people understand it, actually as it stands, even as it stood when Darwin expressed it, and even less as we now may be able to understand it in biology.

Jacques Monod
The false view of evolution as a process of global optimizing has been applied literally by engineers who, taken in by a mistaken metaphor, have attempted to find globally optimal solutions to design problems by writing programs that model evolution by natural selection.